Beverage dispenser for partially frozen beverages with an improved drive and sealing system

ABSTRACT

A beverage dispenser for partially frozen beverages includes at least one bowl for storing a beverage product, with a freezing cylinder positioned in the bowl. The beverage dispenser further includes a cooling system for supplying a cooling medium to the freezing cylinder to cool the beverage product when stored in the bowl, along with a dispenser assembly for dispensing the beverage product from the bowl. The beverage dispenser includes an auger which rotates about the freezing cylinder. A driven hub is positioned on and rotates with respect to the freezing cylinder, and the driven hub engages a rear end portion of the auger. A driver hub is positioned inside of the freezing cylinder and is magnetically coupled to the driven hub, such that rotation of the driver hub causes a corresponding rotation of the driven hub, and thus, rotation of the auger.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation in-part of U.S. patentapplication Ser. No. 13/223,639 filed on Sep. 1, 2011, which claimspriority to U.S. Provisional Patent Application Ser. No. 61/379,813filed on Sep. 3, 2010, the entire disclosures of which is incorporatedherein by reference.

BACKGROUND OF THE INVENTION

The present invention relates to a beverage dispenser, and, moreparticularly, to a beverage dispenser for partially frozen beverageswith an improved drive and sealing system.

In the food service industry, various machines have been developed toproduce, store, and dispense a partially frozen beverage, such as aslush-type beverage. In general, such machines mix water and a flavoredcomponent, freeze the mixture, and then dispense a partially frozenbeverage product with a slush-like consistency. Such machines are oftenreferred to as “granita” machines.

In general, such a granita machine includes a bowl for storing thebeverage product. A freezing cylinder extends through the bowl andhouses evaporator coils (of a refrigeration circuit) or otherrefrigeration means that cools the beverage product to the desiredtemperature. Also located within the bowl is an auger which rotatesabout the freezing cylinder to shave frozen beverage product off of thesurface of the freezing cylinder and to circulate the beverage productwithin the bowl, resulting in the partially frozen or slush-likeconsistency of the beverage product.

In most prior art constructions, a granita machine includes a driveshaft that extends through the center of the freezing cylinder and isconnected to the auger. At the rear of the granita machine, this driveshaft is operably connected to a gear arrangement and motor. Forexample, as shown in FIG. 1, the drive shaft 10 extends through thefreezing cylinder 12, and, at the front end of freezing cylinder 12, thedrive shaft 10 is connected to and drives the auger 14. Thus, such aconstruction requires a shaft seal 16 at the front end of the freezingcylinder 14. This shaft seal 16 is almost continuously submerged in thepartially frozen beverage product and can be prone to leakage, allowingthe beverage product to seep into the interior of the freezing cylinder12. Once the partially frozen beverage product, which typically includeshigh amounts or sugar and is very sticky, gets into the interior of thefreezing cylinder 12, it can be virtually impossible to clean it out ofthe freezing cylinder 12.

Co-pending and commonly owned U.S. patent application Ser. No.13/223,639 thus describes and claims a beverage dispenser for partiallyfrozen beverages with an improved drive and sealing system. The beveragedispenser includes one or more bowls. In each bowl, there is a freezingcylinder, and there is a dispenser assembly at the front end of eachbowl for dispensing the beverage product. In each bowl, there is also anauger which rotates about each freezing cylinder to shave frozenbeverage product off of the surface of the freezing cylinder and tocirculate the beverage product within the respective bowls, resulting inthe partially frozen or slush-like consistency of the beverage product.

The auger in such a beverage dispenser is preferably a unitary membermolded from a thermoplastic material. The auger preferably includes ahelical flange (or flight) that is reinforced by first and secondlongitudinal ribs that extend the length of the auger. At one end, thehelical flange terminates in a cylindrical member that defines aninternal cavity. The freezing cylinder includes a boss extending fromits front surface that is received in the internal cavity defined by thecylindrical member. Thus, once assembled, the position of the augerrelative to the freezing cylinder is maintained, in part, by theconnection of the cylindrical member of the auger to the boss extendingfrom the front surface of the freezing cylinder; however, the auger isstill free to rotate relative to the freezing cylinder.

In each bowl, the auger is driven from the rear, and thus, there is nodrive shaft that extends through the freezing cylinder. Thus, there isno shaft seal in the lower front portion of the dispenser, where itwould be continuously submerged in the partially frozen beverageproduct.

While the beverage dispenser described and claimed in U.S. patentapplication Ser. No. 13/223,639 does address some of the deficiencies ofthe prior art, in some applications, alternative drive systems forrotating the auger may be desirable.

SUMMARY OF THE INVENTION

The present invention is a beverage dispenser for partially frozenbeverages with an improved drive and sealing system.

In a beverage dispenser made in accordance with the present invention,the beverage dispenser includes one or more bowls. In each bowl, thereis a freezing cylinder, and there is a dispenser assembly at the frontend of each bowl for dispensing the beverage product. In each bowl,there is also an auger which rotates about each freezing cylinder toshave frozen beverage product off of the surface of the freezingcylinder and to circulate the beverage product within the bowl,resulting in the partially frozen or slush-like consistency of thebeverage product.

An exemplary auger for use in a beverage dispenser made in accordancewith the present invention is preferably a unitary member molded from athermoplastic material. The auger preferably includes a helical flange(or flight) that is reinforced by first and second longitudinal ribsthat extend the length of the auger. At one end, the helical flangeterminates in a cylindrical member that defines an internal cavity. Thefreezing cylinder includes a boss extending from its front surface thatis received in the internal cavity defined by the cylindrical member.Thus, once assembled, the position of the auger relative to the freezingcylinder is maintained, in part, by the connection of the cylindricalmember of the auger to the boss extending from the front surface of thefreezing cylinder; however, the auger is still free to rotate relativeto the freezing cylinder.

In each bowl, the auger is driven from the rear, and thus, there is nodrive shaft that extends through the freezing cylinder. In this regard,the auger defines a rear end portion at its second end, which, whenassembled, is positioned near the rear of the beverage dispenser. Therear end portion defines an internal cavity with a generally cylindricalvolume. In one exemplary embodiment, multiple teeth extend from the wallsurface of this internal cavity.

The rear end portion of the auger is engaged by a driven hub. In oneexemplary embodiment, the driven hub is an annular structure thatdefines alternating cogs and pockets along its periphery. Onceassembled, the multiple teeth that extend from the wall surface of theinternal cavity in the rear end portion of the auger extend into thepockets. Thus, as the driven hub is rotated, the auger is rotated.

The driven hub is positioned on and rotates around the freezingcylinder. The driven hub is magnetically coupled to a driver hub that ispositioned inside of the freezing cylinder. The driver hub is operablyconnected to a motor, so once the motor is activated, the driver hubbegins rotating. The magnetic coupling of the driven hub and the driverhub thus causes rotation of the driven hub, which, in turn, causesrotation of the auger.

Again, in such a construction, there is no drive shaft that extendsthrough a freezing cylinder, and therefore, there is no shaft seal inthe lower front portion of the dispenser, where it would be continuouslysubmerged in the partially frozen beverage product. Accordingly, thebeverage dispenser of the present invention eliminates the attendantproblems of leakage at a front shaft seal as is common in prior artconstructions.

As an additional benefit, cleaning of the components is much easier ascompared to prior art constructions as a bowl and associated auger canbe readily pulled forward and removed from the dispenser and taken to awash area for cleaning.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of the freezing cylinder, drive shaft, andauger in a prior art construction of a beverage dispenser;

FIG. 2 is a perspective view of an exemplary beverage dispenser made inaccordance with the present invention;

FIG. 3 is a partial perspective view of the exemplary beverage dispenserof FIG. 2, but with one bowl hidden from view to better illustrate thefreezing cylinder, auger, and other internal components;

FIG. 4 is another partial perspective view of the exemplary beveragedispenser of FIG. 2, but with both bowls hidden from view to betterillustrate the freezing cylinders, augers, and other internalcomponents;

FIG. 5 is an sectional view of the exemplary beverage dispenser of FIG.2, illustrating the relationship between the freezing cylinder, auger,the driven hub, and the driver hub;

FIG. 6 is a perspective view of one of the augers of the exemplarybeverage dispenser of FIG. 2;

FIG. 7 is a partial perspective view of the exemplary beverage dispensersimilar to FIG. 3, but with the auger hidden from view to betterillustrate the freezing cylinder and the driven hub;

FIG. 8 is a partial perspective view of the exemplary beverage dispensersimilar to FIG. 7, but with the auger and the freezing cylinder hiddenfrom view to illustrate the relationship between the driver hub and thedriven hub;

FIG. 9 is an end view of one auger, a driver hub, and a driven hub ofthe exemplary beverage dispenser of FIG. 2;

FIG. 10 is an end view of the driver hub and the driven hub of FIG. 9,with the respective magnets of the driver hub and the driven hub shownin phantom; and

FIG. 11 is a schematic view of the cooling system in the exemplarybeverage dispenser of FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is a beverage dispenser for partially frozenbeverages with an improved drive and sealing system.

FIG. 2 is a perspective view of an exemplary beverage dispenser made inaccordance with the present invention. The exemplary beverage dispenser20 has two separate bowls 24 a, 24 b with lids 25 a, 25 b, and there isa dispenser assembly 40 a, 40 b at the front end of each bowl 24 a, 24 bfor dispensing the beverage product. However, it should be recognizedthat a beverage dispenser made in accordance with the present inventioncould have any number of bowls and associated dispensing assemblieswithout departing from the spirit and scope of the present invention.

FIG. 3 is a partial perspective view of the same exemplary beveragedispenser 20, but with one bowl 24 a hidden from view to betterillustrate some of the internal components of the beverage dispenser 20.FIG. 4 is another partial perspective view of the exemplary beveragedispenser 20 of FIG. 2, but with both bowls 24 a, 24 b hidden from viewto better illustrate some of the internal components of the beveragedispenser 20.

As shown in FIGS. 3 and 4, in this exemplary beverage dispenser 20, ineach bowl 24 a, 24 b, there is a freezing cylinder 30 a, 30 b, which, asmentioned above, is typical of prior art constructions. As is alsotypical in prior art constructions, in each bowl 24 a, 24 b, there is anauger 50 a, 50 b which rotates about the respective freezing cylinder 30a, 30 b to shave frozen beverage product off of the surface of thefreezing cylinder 30 a, 30 b and to circulate the beverage productwithin the respective bowls 24 a, 24 b, resulting in the partiallyfrozen or slush-like consistency of the beverage product.

FIG. 6 is a perspective view of one of the augers 50 a of the exemplarybeverage dispenser 20, and FIG. 7 is a partial perspective view of theexemplary beverage dispenser 20 that perhaps best illustrates thefreezing cylinder 30 a.

As shown in FIG. 6, the auger 50 a is preferably a unitary member andmolded from a thermoplastic material. The auger 50 a includes a helicalflange (or flight) 52 a that is reinforced by first and secondlongitudinal ribs 54 a, 55 a that extend the length of the auger 50 a.At one end, the helical flange 52 a terminates in a cylindrical member56 a that defines an internal cavity. As shown in FIG. 7, the freezingcylinder 30 a includes a boss 32 a extending from its front surface thatis received in the internal cavity defined by the cylindrical member 56a. Thus, once assembled, the position of the auger 50 a relative to thefreezing cylinder 30 a is maintained, in part, by the connection of thecylindrical member 56 a of the auger 50 a to the boss 32 a extendingfrom the front surface of the freezing cylinder 30 a; however, the auger50 a is still free to rotate relative to the freezing cylinder 30 a.

In each bowl 24 a, 24 b, the auger 50 a, 50 b is driven from the rear,and thus, there is no drive shaft that extends through the respectivefreezing cylinders 30 a, 30 b. Specifically, as shown in FIGS. 3-6, eachauger 50 a, 50 b is formed with an integral rear end portion 58 a, 58 bat its second end, which, when assembled, is positioned near the rear ofthe beverage dispenser 20. Referring now to FIG. 9, each rear endportion 58 a defines an internal cavity 60 a with a generallycylindrical volume. Furthermore, in this exemplary embodiment, multipleteeth 62 a are molded into and extend from the wall surface of thisinternal cavity 60 a, the importance of which is further describedbelow.

Referring still to FIG. 9, the rear end portion 58 a of the auger 50 ais engaged by a driven hub 70 a, which is an annular structure thatdefines alternating cogs 72 a and pockets 74 a along the periphery ofthe driven hub 70 a. As shown in FIG. 9, once assembled, the multipleteeth 62 a that extend from the wall surface of the internal cavity 60 ain the rear end portion 58 a of the auger 50 a extend into the pockets74 a defined along the periphery of the driven hub 70 a. Thus, as thedriven hub 70 a is rotated, the auger 50 a is rotated.

Referring now to FIG. 7, where the auger 50 a has been hidden from view,the driven hub 70 a is positioned on and rotates around the freezingcylinder 30 a. Referring now to FIG. 8, where the auger 50 a and thefreezing cylinder 30 a have been hidden from view, along with thesectional view of FIG. 5, the driven hub 70 a is magnetically coupled toa driver hub 80 a that is positioned inside of the freezing cylinder 30a. With respect to the magnetic coupling of the driven hub 70 a and thedriver hub 80 a, and as shown in FIG. 10, a plurality of magnets 75 a ishoused within the driven hub 70 a, and a corresponding plurality ofmagnets 85 a is housed within the driver hub 80 a. In this exemplaryembodiment, each of the driven hub 70 a and the driver hub 80 a housessixteen magnets that face and engage each other through the wall of thefreezing cylinder 30 a. In any event, as a result of the magneticcoupling, rotation of the driver hub 80 a causes a correspondingrotation of the driven hub 70 a.

Returning to the sectional view of FIG. 5, the driver hub 80 a isoperably connected to the motor 88, so once the motor 88 is activated,the driver hub 80 a begins rotating. The magnetic coupling of the drivenhub 70 a and the driver hub 80 a thus causes rotation of the driven hub70 a, which, in turn, causes rotation of the auger 50 a. However, itshould be recognized that because there is only a magnetic couplingbetween the driven hub 70 a and the driver hub 80 a, as opposed to amechanical coupling, if over-frozen beverage product or another obstacleimpedes rotation of the auger 50 a, the magnetic coupling will “break”before the motor 88 is overloaded.

As mentioned above, in such a construction, there is no drive shaft thatextends through the respective freezing cylinders 30 a, 30 b, andtherefore, there is no shaft seal in the lower front portion of thebeverage dispenser 20, where it would be continuously submerged in thepartially frozen beverage product. Accordingly, the beverage dispenser20 of the present invention eliminates the attendant problems of leakageat a front shaft seal as is common in prior art constructions.

As an additional benefit, in such a construction, cleaning of thecomponents is much easier as compared to prior art constructions as eachbowl 24 a, 24 b and each auger 50 a, 50 b can be readily pulled forwardand removed from the beverage dispenser 20 and taken to a wash area forcleaning. Specifically, and as shown in the sectional view of FIG. 5, inassembling the beverage dispenser 20, the auger 50 a simply slips overthe freezing cylinder until it engages the driven hub 70 a. Similarly,the bowl 24 a has a circular rear opening that allows it to be similarlyslipped over the freezing cylinder 30 a and the auger 50, until a lip 26a that circumscribes the rear opening contacts and engages a sealinggasket 28 a.

Finally, it should be recognized that an exemplary beverage dispensermade in accordance with the present invention would include a typicalcooling system to produce the necessary refrigeration circuit. In thisexemplary embodiment, a flooded evaporator approach is used.Specifically, and as shown in FIG. 5, each freezing cylinder 30 a, 30 bhas a double-walled construction, such that a cooling medium can flow inthe space between the walls. The cooling medium is delivered into thisspace by a capillary tube 35 a, 35 b associated with each freezingcylinder 30 a, 30 b. The capillary tubes 35 a, 35 b are in fluidcommunication with certain cooling components housed in a lower portionof the beverage dispenser 20. For example, as shown in the schematicview of FIG. 11, the components of the cooling system 90 may include acompressor 100, a condenser 102, a filter/dryer 104, the above-describedcapillary tubes 35 a, 35 b (or other refrigerant control device), and asuction line 110. As is common in such cooling systems, the compressor100 compresses the cooling medium, preferably a refrigerant gas such asR404a (a commercially available hydrofluorocarbon refrigerant), to raisethe temperature and stored energy of the cooling medium. Therefore, thecooling medium exits the compressor 100 and enters the condenser 102 asa hot, high pressure gas. In the condenser 102, the heat from thepressurization of the cooling medium is dissipated, and the coolingmedium reverts to a liquid form, but remains at a high pressure. Thecooling medium then passes through a filter drier 104, which is designedto filter out contaminants and dry the cooling medium to prevent iceformation. As it exits the filter drier 104, the cooling medium isseparated into two streams, one associated with each freezing cylinder30 a, 30 b. In each case, the cooling medium passes through to therespective capillary tube 35 a, 35 b associated with each freezingcylinder 30 a, 30 b. In this exemplary embodiment, such flow into eachcapillary tube 35 a, 35 b is controlled by a solenoid valve 105 a, 105b. In any event, each capillary tube 35 a, 35 b serves as apressure-reducing device and meters the cooling medium into the spacebetween the walls of the respective freezing cylinders 30 a, 30 b.Because of the pressure drop, the cooling medium evaporates, absorbingheat as it does so. By the time the cooling medium exits the freezingcylinders 30 a, 30 b, returning to the compressor 100 through a suctionline 110, it again is a cool, low-pressure gas.

One of ordinary skill in the art will also recognize that additionalembodiments are possible without departing from the teachings of thepresent invention. This detailed description, and particularly thespecific details of the exemplary embodiment disclosed therein, is givenprimarily for clarity of understanding, and no unnecessary limitationsare to be understood therefrom, for modifications will become obvious tothose skilled in the art upon reading this disclosure and may be madewithout departing from the spirit or scope of the invention.

What is claimed is:
 1. A beverage dispenser for partially frozenbeverages, comprising: at least one bowl for storing a beverage product;a freezing cylinder positioned in the bowl; a cooling system forsupplying a cooling medium to the freezing cylinder to cool the beverageproduct when stored in the bowl; a dispenser assembly for dispensing thebeverage product from the bowl near a front of the beverage dispenser;an auger which rotates about the freezing cylinder, the auger includinga first end positioned near the front of the beverage dispenser and asecond end positioned near a rear of the beverage dispenser, and theauger defining a rear end portion at the second end of the auger withthe rear end portion of the auger defining an internal cavity with agenerally cylindrical volume, with multiple teeth extending from a wallsurface of the internal cavity; a driven hub that is positioned on andadjacent an external surface of the freezing cylinder and rotates aroundthe freezing cylinder, the driven hub engaging the multiple teeth of therear end portion of the auger; and a driver hub that is positionedinside of the freezing cylinder and is magnetically coupled to thedriven hub, such that rotation of the driver hub causes a correspondingrotation of the driven hub; wherein the auger and the driven hub areconfigured to slide along the length of the freezing cylinder, thusfacilitating the removal of the auger and the driven hub from thefreezing cylinder.
 2. The beverage dispenser as recited in claim 1,wherein the driver hub is operably connected to a motor.
 3. A beveragedispenser, for partially frozen beverages, comprising: at least one bowlfor storing a beverage product; a freezing cylinder positioned in thebowl; a cooling system for supplying a cooling medium to the freezingcylinder to cool the beverage product when stored in the bowl; adispenser assembly for dispensing the beverage product from the bowlnear a front of the beverage dispenser; an auger which rotates about thefreezing cylinder, the auger including a first end positioned near thefront of the beverage dispenser and a second end s positioned near arear of the beverage dispenser, and the auger defining a rear endportion at the second end of the auger; a driven hub that is positionedon and adjacent an external surface of the freezing cylinder and rotatesaround the freezing cylinder, the driven hub engaging the rear endportion of the auger; and a driver hub that is positioned inside of thefreezing cylinder and is magnetically coupled to the driven hub, suchthat rotation of the driver hub causes a corresponding rotation of thedriven hub; wherein the rear end portion of the auger defines aninternal cavity with a generally cylindrical volume, with multiple teethextending from a wall surface of the internal cavity for engaging thedriven hub; wherein the driven hub defines alternating cogs and pocketsalong its periphery, such that the multiple teeth that extend from thewall surface of the internal cavity in the rear end portion of the augerextend into the pockets; and wherein the auger and the driven hub areconfigured to slide along the length of the freezing cylinder, thusfacilitating the removal of the auger and the driven hub from thefreezing cylinder.
 4. The beverage dispenser as recited in claim 1,wherein the auger is a unitary member.
 5. The beverage dispenser asrecited in claim 4, wherein the auger is molded from a thermoplasticmaterial.
 6. The beverage dispenser as recited in claim 1, wherein theauger includes a helical flange.
 7. The beverage dispenser as recited inclaim 6, wherein the auger further includes at least two longitudinalribs that extend the length of the auger.
 8. The beverage dispenser asrecited in claim 6, wherein, at the first end of the auger, the helicalflange terminates in a cylindrical member that defines an internalcavity for receiving a boss extending from a front surface of thefreezing cylinder.
 9. A beverage dispenser for partially frozenbeverages, comprising: a first bowl for storing a first beverageproduct; a first freezing cylinder positioned in the first bowl; a firstauger which rotates about the first freezing cylinder, the first augerincluding one end positioned near a front of the beverage dispenser andanother end positioned near a rear of the beverage dispenser, and thefirst auger defining a rear end portion at the end of the first augerpositioned near the rear of the beverage dispenser with the rear endportion of the first auger defining an internal cavity with a generallycylindrical volume, with multiple teeth extending from a wall surface ofthe internal cavity; a first driven hub that is positioned on andadjacent an external surface of the first freezing cylinder and rotatesaround the first freezing cylinder, the first driven hub engaging themultiple teeth of the rear end portion of the first auger; a firstdriver hub that is positioned inside of the first freezing cylinder andis magnetically coupled to the first driven hub, such that rotation ofthe first driver hub causes a corresponding rotation of the first drivenhub; a first dispenser assembly for dispensing the first beverageproduct from the first bowl near the front of the beverage dispenser; asecond bowl for storing a second beverage product; a second freezingcylinder positioned in the second bowl; a second auger which rotatesabout the second freezing cylinder, the second auger including one endpositioned near a front of the beverage dispenser and another endpositioned near a rear of the beverage dispenser, and the second augerdefining a rear end portion at the end of the second auger positionednear the rear of the beverage dispenser, with the rear end portion ofthe second auger defining an internal cavity with a generallycylindrical volume, with multiple teeth extending from a wall surface ofthe internal cavity; a second driven hub that is positioned on andadjacent an external surface of the second freezing cylinder and rotatesaround the second freezing cylinder, the second driven hub engaging themultiple teeth of the rear end portion of the second auger; a seconddriver hub that is positioned inside of the second freezing cylinder andis magnetically coupled to the second driven hub, such that rotation ofthe second driver hub causes a corresponding rotation of the seconddriven hub; a second dispenser assembly for dispensing the secondbeverage product from the second bowl near the front of the beveragedispenser; and a cooling system for supplying a cooling medium to thefirst freezing cylinder and the second freezing cylinder to cool thefirst beverage product stored in the first bowl and the second beverageproduct stored in the second bowl; wherein the first auger and the firstdriven hub are configured to slide along the length of the firstfreezing cylinder, thus facilitating the removal of the first auger andthe first driven hub from the first freezing cylinder, and wherein thesecond auger and the second driven hub are configured to slide along thelength of the second freezing cylinder, thus facilitating the removal ofthe second auger and the second driven hub from the second freezingcylinder.